Law is a set of rules created and enforced by social or governmental institutions to regulate behavior. Its precise definition is a matter of longstanding debate. It has been variously described as a science and as the art of justice. It is an essential part of human societies. Law shapes politics, economics, history and society in many ways. For example, it can help people to solve conflicts peacefully. It can also ensure that governments and police are accountable to the public. But modern military, policing and bureaucratic power over the lives of ordinary people pose special problems for accountability that Max Weber and other writers could not have predicted.
The law can be divided into civil and common laws, with the latter based on legal precedent established in the courts. Civil law jurisdictions are found on all continents, covering about 60% of the world population. Their laws are largely derived from Roman law, with influences from canon and local customs. They tend to be more secular than common law systems, although religious laws have played a role in the past.
Civil law encompasses all the legal matters that affect the daily life of people. For example, property law deals with issues such as ownership and titles to land; contract law deals with agreements between private parties; and tax law deals with taxable income and capital gains. It can also include criminal law, which deals with prosecution of crimes such as murder and theft.
In addition, there is family law, which includes divorce and custody proceedings; social security law, which deals with claiming benefits such as jobseekers allowances or housing allowances; and transactional law, which covers the laws that govern commercial activities such as banking and finance. Dispute resolution law is another area of the practice of law, which involves helping people resolve their disputes, for example, by mediation or arbitration.
Even in a well-ordered society, disagreements between people can arise. The law provides a way to settle those disagreements peacefully by referring them to the courts. For example, if two people claim to own the same piece of land, they can go to court to decide who owns it. The law can also ensure that government officials and police are accountable to the public by ensuring they act according to the laws of the country.
There is a strong scientific element to the study of law. The laws of physics and biology, for example, provide a framework within which the law can be formulated. It is the role of the legal scholar to understand these principles and to interpret them in a way that makes sense for the contemporary world. In the end, however, the law is contingent on the shape of the physical world and on humans, who must apply their own sense of fairness to determine the laws that are applied in their society. This is known as the Holmesian definition of law. The idea behind it is that as participants assign true or false values to mathematically undecidable propositions, the results of these decisions are recorded and become law.